Which one of the following is an s-block element?

Options

A. Aluminium
B. Chromium
C. Niobium
D. Potassium

Answer

To determine which of the given options is an s-block element, we can follow these steps:

### Step 1: Understand the s-block elements
The s-block elements are found in Group 1 and Group 2 of the periodic table. Group 1 includes alkali metals, and Group 2 includes alkaline earth metals.

### Step 2: List the options provided
The options given are:
1. Aluminum
2. Chromium
3. Niobium
4. Potassium

### Step 3: Identify the group of each element
- **Aluminum (Al)**: This element is in Group 13 (P-block).
- **Chromium (Cr)**: This element is in Group 6 (D-block).
- **Niobium (Nb)**: This element is in Group 5 (D-block).
- **Potassium (K)**: This element is in Group 1 (S-block).

### Step 4: Conclusion
Among the given options, **Potassium (K)** is the only s-block element.

### Final Answer
Potassium is the s-block element.

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